TGS’ least-squares RTM is the industry-leading depth imaging technology that refines the conventional RTM image toward true reflectivity.

It overcomes the shortcomings of conventional migration algorithms via iterative least-squares inversion in order to gradually correct migration errors. Compared to conventional depth migration algorithms, LSRTM generates superior seismic images with the advantages including balanced amplitudes, less migration artifacts, higher spatial resolution, and improved images for steep dips and complex structures. LSRTM is implemented with two objectives using different workflows: one is to produce a broadband image with higher resolution, and the second is to improve poorly illuminated areas. The first objective is usually focused on areas of interest in shallower zones, and the second objective would be focused on deeper zones, such as subsalt.

For brief review and examples about LSRTM, please see the following papers published by TGS researchers:

Zeng C., S. Dong, and B. Wang, 2014, “Least-squares reverse time migration: Inversion-based imaging toward true reflectivity”, The Leading Edge, 33(9), 962–964, 966, 968. doi: 10.1190/tle33090962.1

Zeng C., S. Dong, and B. Wang, 2016, “Adaptive least-squares RTM with applications to subsalt imaging”, The Leading Edge, 35(3), 253-257. doi: 10.1190/tle35030253.1